busybox

hush: fix IFS handling in read

$ echo "X:Y:" | (IFS=": " read x y; echo "|$x|$y|")
|X|Y|
$ echo "X:Y  :  " | (IFS=": " read x y; echo "|$x|$y|")
|X|Y|

function                                             old     new   delta
shell_builtin_read                                  1320    1426    +106

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>